Tanga is offering the OtterBox Prefix Series Case for iPhone 5 for only $15 + $4 shipping (Reg. $25). The Prefix series features a one-piece design with a shock-resistant silicone exterior. Its internal polycarbonate skeleton supports and protects the iPhone while an included self-adhesive screen protector ensures protection from scratches. The Prefix’s unibody case allows for one-step installation and a convenient, light weight of 1.44 ounces.